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| author | Mika Westerberg <mika.westerberg@linux.intel.com> | 2018-09-27 23:57:14 +0200 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2018-10-02 23:04:40 +0200 |
| commit | 26ad34d510a87fc65caeb48fa85cce58d2477a88 (patch) | |
| tree | 875312464f915fc088e0d258e97fc4504e249582 /drivers/acpi/property.c | |
| parent | ACPI / property: Allow multiple property compatible _DSD entries (diff) | |
| download | linux-26ad34d510a87fc65caeb48fa85cce58d2477a88.tar.xz linux-26ad34d510a87fc65caeb48fa85cce58d2477a88.zip | |
PCI / ACPI: Whitelist D3 for more PCIe hotplug ports
In order to have better power management for Thunderbolt PCIe chains,
Windows enables power management for native PCIe hotplug ports if there is
the following ACPI _DSD attached to the root port:
Name (_DSD, Package () {
ToUUID ("6211e2c0-58a3-4af3-90e1-927a4e0c55a4"),
Package () {
Package () {"HotPlugSupportInD3", 1}
}
})
This is also documented in:
https://docs.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports#identifying-pcie-root-ports-supporting-hot-plug-in-d3
Do the same in Linux by introducing new firmware PM callback
(->bridge_d3()) and then implement it for ACPI based systems so that the
above property is checked.
There is one catch, though. The initial pci_dev->bridge_d3 is set before
the root port has ACPI companion bound (the device is not added to the PCI
bus either) so we need to look up the ACPI companion manually in that case
in acpi_pci_bridge_d3().
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/property.c')
| -rw-r--r-- | drivers/acpi/property.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c index 90ba9371bae6..8c7c4583b52d 100644 --- a/drivers/acpi/property.c +++ b/drivers/acpi/property.c @@ -28,6 +28,9 @@ static const guid_t prp_guids[] = { /* ACPI _DSD device properties GUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */ GUID_INIT(0xdaffd814, 0x6eba, 0x4d8c, 0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01), + /* Hotplug in D3 GUID: 6211e2c0-58a3-4af3-90e1-927a4e0c55a4 */ + GUID_INIT(0x6211e2c0, 0x58a3, 0x4af3, + 0x90, 0xe1, 0x92, 0x7a, 0x4e, 0x0c, 0x55, 0xa4), }; static const guid_t ads_guid = |